Measurements of Weight Bearing Asymmetry Using the Nintendo Wii Fit Balance Board Are Not Reliable for Older Adults and Individuals With Stroke.
Derek M Liuzzo, Denise M Peters, Addie Middleton and 4 others
PMID 26288237WHAT IT FOUND
Wii Fit balance board weight bearing asymmetry readings were moderately consistent but had large error.
For older adults and stroke, changes must exceed 8.8% or 13.6% to be confident, so the board is not recommended for this assessment with factory settings.
Key findings
01Weight bearing asymmetry measurements were moderately reliable in older adults (ICC = 0.59) and in individuals with stroke (ICC = 0.60).
02The measurement error was large: weight bearing asymmetry would need to change by more than 8.8% for older adults and 13.6% for individuals with stroke before a true change could be confirmed.
03The authors conclude that the board should be used with caution and is not recommended for assessing weight bearing asymmetry in these populations.
STILL TO COME
How it was doneWhat they foundWhat it means for PTs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
Two outliers were removed from the older adult group to obtain a normal weight bearing asymmetry distribution, so the analysed older adult sample was 41. The stroke group had 41 participants, but 127 individual observations were analysed because participants were measured multiple times in a larger study. Only two trials were analysed, and no practice trials were given, so the reliability estimate may not reflect what happens when clinicians repeat testing after familiarisation. Sensory testing was not performed on older adults, and sensory impairment could affect weight bearing asymmetry. The Wii Fit readout time varied, and error messages could occur when participants moved excessively.
Declared interests
The paper states there are no conflicts of interest.
The easy way to misread this
Do not read a small change in Wii Fit weight bearing asymmetry as a true change. The paper says weight bearing asymmetry must change by more than 8.8% for older adults and more than 13.6% for individuals with stroke before a clinician can be 95% confident that a true change occurred.